\begin{tikzpicture}
	\tkzDefPoints{0/0/A, 1.5/0/B, -1.5/0/x}
	\tkzDrawSegment(A,B)
	\tkzDrawSegment[dashed](A,x)
	\tkzDrawPoints[fill=black](A,B)
	\tkzLabelPoints[above](A,B)
\end{tikzpicture}

